Network data centers are facilities which typically house computer systems (e.g., banks of servers) and telecommunications equipment used to allow the computer systems to communicate among each other and with other data centers via fiber optic links. Network data centers typically communicate via a data center interconnect (DCI) device which interfaces the data center (DC) to a computer communications network. For example, a DCI may include one or more network switches which provide interconnectivity within the DC, transmit outbound traffic from the DC over a long haul fiber optic cable to another DC, and transmit inbound traffic from another DC to the equipment inside the DC. Network traffic that transits a DCI can be broadly classified into three categories based on latency requirements—(a) delay-sensitive, short flow interactive traffic, (b) larger transfers which require delivery within certain time period, and (c) background traffic that is more throughput-sensitive; i.e., which require a number of messages to be delivered successfully within a given time.
Packet buffering in the DCI affects all traffic flows; however, the impact on time sensitive short flows can be severe if such flows are queued behind long flows in the buffer. In order to meet timeliness guarantees of such a diverse stream of flows, it has been posited that buffer occupancies should be persistently low while maintaining throughput. Conventional equipment however fails to keep buffer occupancies low globally. For example, trading off network bandwidth to reduce latency has been proposed within data centers, however these techniques are application specific, require hardware modifications, and do not consider global constraints across flows and devices. Accordingly, using current techniques, improving latency at one data center in this way can increase buffering in other connected data centers.